1. Technical Field
The present invention relates to an apparatus for projecting a space image, more specifically to projecting a space image to a space through a projecting unit.
2. Background Art
A space image renders a depth, unlike a two-dimensional flat image. When the space image is recognized by a person through both eyes, the person can sense a three-dimensional effect. An apparatus for projecting a space image provides the three-dimensional effect, as if the person is looking at an actual object, by projecting the space image as described above. Today, the space image is often projected by 3D display technologies such as a polarization method, a shutter glass method, a parallax barrier method, a lenticular method, etc., but these methods either require a special glasses or restrict the viewing angle. Other methods for projecting a space image include using a convex lens, a concave mirror, a transflective mirror, etc. However, while the convex lens and the concave mirror project the image outside the screen and thus allow the views to touch the image, their viewing angles are quite restricted. Using the transflective mirror has a projecting monitor positioned in the direction of the view, and thus the three-dimensional effect is diminished by the presence of the monitor. Moreover, there are many structural limitations with the transflective mirror. For example, the transflective mirror needs to be positioned at an angle of 45 degrees.